Improvement in revolving stereoscopes



i ing substance.

Un'rrnn STATES.

Pn'rniwr OFFICE.

JONATHAN YV. CADVELL, OF NORTH READING, MASSACHUSETTS.

IMPROVEMENT IN REVOLVING STEREOSCOPES. .i

Speciiicntion forming part of Letters Patent No. 146,l61, dated January6,1824; apl lcaticn filed May 5, 1873. .i

To all 'whom it may concern:

Be it known that I, JONATHAN W. CAD- WELL, of North Reading, in thecounty of Mid dlesex and State of Massachusetts, have invented certainImprovements in Stereoscopes, of which. the following is aspecification:

Figure l of the accompanying drawing is a central vertical longitudinalsection, and Fig. 2 is a central vertical transverse section, of myimproved stereoscope-case. Fig. 3 is a part in detail of the same.

This invention relates to that class of stereoscopes in which the viewsare pivoted to a revolving horizontal shaft in such manner as, whenrevolved, to successively expose each picture as it reaches a verticalposition over the shaft, those in front falling by gravitation, so as toexpose the entire surface of the view, which is held by a suitablespring-detent. My invention has for its object to provide a stereoscopein which a greater number of views shall be held upon a single shaftthan is usually done, and yet allow sufficient fall of the views, afterpassing a vertical line through the shaft, to expose the entire surfaceof the succeeding view. `To this end it consists in the peculiarconstruction of the view holders or clamps, enabling them to lie closelytogether,.and their arrangement on a peculiarly-constructed shaft orroller, as I will now proceed to describe.

Inthe drawings, c represents a stereoscopecase, formed with suitableeye-pieces b b', arranged as usual, and provided on the top with hingedlids c, lined with tin-foil or other reflect- Within the case a,extending transversely, is a roller or axle, d, whose ends d aresupported by and turn in the sides of the ease a. At each end of theroller d are attached two parallel plates or disks, e e', formed with aseries of perforations, f, near the edge of the circumference, in whichthe ends of transverse rods g are held and allowed toturn. Between theparallel disks c c and el e are side flaps or clamps h h', that are bentat the bottom, so as to turn on and be held by the rods g', and form twooutward-extending portions or arms. The back portion or arm of the iiapsis curved at the upper portion and rounded at the edge, as shown, toprevent the interference of one series of iiaps with the other in theirrotation, and to receive the ends of stationary rods g, that connect theflaps on one side with the flaps on the opposite side," and extendshorizontally across the top, and is rounded on the front edge, andformed with a downward-extending lip or catch, 71. that turns over andholds the top of the front portion or arm of the iiaps. On the top ofthe ilaps being raised, the catch is unloosed and the front armsreleased for the admission of the views, whose sides are held betweenthe front and back portions or arms of the ilaps, from which the viewsare readily 4withdrawn by raising the tops of the flaps and releasingthe lips or catches h from the front arms. The bottoms of the flaps h h'are formed at front and back with double-reversed curves, as shown inFig. 3, so that the convex portion of one flap will impinge against theconcave portion of the other iiapwhen together, and thus allow a greaternumber of iiaps to be connected with the plates e e', and permit oftheir rotation without the interference of one with the other. Theroller d is provided with and operated by a suitable crank or knob, 7c,arranged' on one or both sides of the case a. Within the case a, on eachside, at the top, is a bent rod or spring, l, held by a screw or stem,l. This rod or spring is only necessary for the use of transparentviews, and is so bent or arranged as to allow the passage of the rodsand views in one direction, and prevent their falling backward, so thatwhen the desired Aview is brought properly in sight by the rotation ofthe axle cl it will be prevented, by the spring or rod l, from fallingback.

The rods g may, if desired, be attached to the top of the iiaps h h' onthe outside.

By my improvements, as shownV in the accompanying drawings, and ashereinabove described, it will readily be seen that a great number ofiiaps for the reception of the views may be arranged within the case,requiring but a small space for their operation, thus enabling a smallerbox than ordinary to be used; and as the several operative parts aresimple and inexpensive in con struction and cost, the apparatus can befurnished at less expense than the larger and ordinarily-constructedstereoscopes of similar description. Moreover, by the arrangement andoperation of the flaps IL h', as hereinabove described and shown, itwill be seen that they arereadily operated without the interference ofone series with the other; and that the views are readily adjusted andsecurely heldin or easily Withdrawn from the Haps and that theobjections occasioned hitherto by the interfering and falling out of theviews is obviated.

Having thus fully described my improvements, what I claim as myinvention7 and de- .sire to have secured to me by Letters Patent7 1sl.In a stereoseope for revolving views7 the clamps 71l h pivoted tolongitudinal rods g on a revolving axle, said clamps being adapted tofit snugly together at their inner ends by means of reverse curves oreorrugations7 sub- JONATHAN WI. CADVELI'.

Witnesses:

CARROLL D. VRIGHT, SAML, M. BARTON.

